How to remove face lightning problems from my 3D scenes?

Hi everyone, I hope you are doing well!

I noticed that in my scenes, some lighting problems with triangular faces are common, as seen in the image below.

The same object viewed in Blender doesn’t seem to have this problem.

Could someone tell me what causes this type of problem? How can I resolve it?

Thank you for your attention!

do you have ngons in your blender scene?

while blender might know how to work with its own ngons , on export, they are triangulated and might be the cause of issues like this.

Also , your comparison is showing blenders viewport without proper shading as done when rendering. Have you rendered this object in blender yet?

The model looks like a parametric import ( i know the look ) meaning it was a Format from any of the parametric apps like autocad , solidworks , rhino etc… ( STL etc … )

99.9% of the time, the automatic conversion from parametric to geometrical is never good and always in some way produces bad topology like long thin triangles , non manifold , non planar, overlapping faces.

It depends on the model. The poly counts will also mostly never be good for realtime

show us the topology :wink:


Thanks @shaderbytes. Thanks so much for the knowledge. I believe the problem is exactly what you said since I export to OBJ with triangular faces. I noticed that when reimporting the obj in Blender, the same problem happens:


Is there anything I can do on the Babylon side to reduce this effect without changing the model exported topology?

So there could be many things at play here but firstly just know that these are shading artifacts that are caused by smooth shading algorithms and bad topology… is this the topology before export?

Two things you can try ,

in the object data inspector ( green triangle of points )

  1. check that the model does not have “auto smooth” set in under the “normals” section.

  2. check it doesnt have a custom property for split normals under the “Custom Properties” section , if it does , remove it.

these are just shots in the dark , as mentioned many things could be at play.